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 A137366 Subsequence of A137365 where it is possible to choose p1, p2, p3 so that p1+p2+p3 = prime. 3
 1483, 5381, 6271, 7229, 9181, 11897, 13103, 13841, 14489, 17107, 20357, 25747, 26711, 27917, 30161, 30259, 31247, 32579, 36677, 36899, 36901, 42083, 48817, 54181, 55511, 55691, 56377, 57637, 64151, 66347, 69389, 75167, 76031, 76123 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 36161 is the first number that is in A137365 but not in the present sequence. See A138556. LINKS R. J. Mathar, Table of n, a(n) for n = 1..44 EXAMPLE 1483=3^3+5^3+11^3, 3+5+11=17; 7229=3^3+7^3+19^3, 3+7+19=29. MATHEMATICA Array[r, 99]; Array[y, 99]; For[i = 0, i < 10^2, r[i] = y[i] = 0; i++ ]; z = 4^2; n = 0; For[i1 = 1, i1 < z, a = Prime[i1]; a2 = a^3; For[i2 = i1 + 1, i2 < z, b = Prime[i2]; b2 = b^3; For[i3 = i2 + 1, i3 < z, c = Prime[i3]; c2 = c^3; p = a2 + b2 + c2; p3 = a + b + c; If[PrimeQ[p] && PrimeQ[p3], Print[a2, " + ", b2, " + ", c2, " = ", p, "; ", a, " + ", b, " + ", c, " = ", p3]; n++; r[n] = p]; i3++ ]; i2++ ]; i1++ ]; Sort[Array[r, 71]] lst = {}; Do[q = Prime@a; r = Prime@b; s = Prime@c; p = q^3 + r^3 + s^3; t = q + r + s; If[PrimeQ@p && PrimeQ@t, AppendTo[lst, p]], {a, 14}, {b, a - 1}, {c, b - 1}]; Take[Sort@lst, 35] - Robert G. Wilson v, Apr 13 2008 CROSSREFS Cf. A137365, A138556. Sequence in context: A204037 A035864 A137365 * A045008 A104742 A051260 Adjacent sequences:  A137363 A137364 A137365 * A137367 A137368 A137369 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Apr 09 2008, Apr 14 2008 STATUS approved

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